The people of the Middle Ages, to their great credit, understood that our lives are a battlefield, that spiritual warfare was an ever present reality. Wanting to do battle with the devil, and knowing that the core of his sin is grounded in pride, they determined a bit of a psy-op, some psychological warfare by presenting him neither as a great beauty nor as a dreadful specter but as a fool. This is the source of this now common image.
Now the serpent is more crafty than any of the beasts of the field. I have no idea if being mocked sent Old Scratch off to lick his wounds. I do know that he took this assault on his pride and used it to his advantage. He took that silly image designed to deny his beauty and his power and used it to deny his existence. Moderns, when they think of the devil, do not think of a great and malevolent force, but a silly cartoon. Who would be silly enough to believe in such a creature, much less be on guard against it? What’s he going to do, kick us with his hooves?
It was CS Lewis who argued, in the introduction to his masterful Screwtape Letters, that the devil vacillates between two strategies. In the one he presents himself as dreadful and omnipresent. In the other he hides himself completely. It may well be that he first shifted from the first strategy to the second just about the time we started painting him as a fool.
The devil is not a comic book character. Angels are not sweet and cuddly babies. Both, however, are real, powerful and active. Both are not to be trifled with. It is true that when we resist the devil he must flee, that He who is in us is greater than he who is against us. It is also true, however, that even the arch-angel Michael knew better than to treat the devil like a plaything (Jude 1:9). The key, it seems, is to neither walk in fear of the enemy of God whose head was crushed by the wounded heel of Jesus, nor to forget that he was the highest of all God’s creations. As long as the Father wills it to be so, Satan will be our enemy. As long as Jesus, Whose kingdom shall know no end, reigns, he will be an enemy on a leash.